Xerxes

Xerxes, a king of Persia, son of Darius I., whom he succeeded on the
throne in 485 B.C.; in his ambition to subdue Greece, which, after
suppressing a revolt in Egypt, he in 481 essayed to do with an immense
horde of men both by sea and land, he with his army crossed the
Hellespont by means of a bridge of boats, was checked for a time at
Thermopylæ by Leonidas and his five hundred, advanced to Athens to see
his fleet destroyed at Salamis by Themistocles, fled at the sight by the
way he came, and left Mardonius with 300,000 men to carry out his
purpose, but, as it happened, to suffer defeat on the fatal field of
Platæa in 479, and the utter annihilation of all his hopes; the rest of
his life he spent in obscurity, and he was assassinated in 465 by
Artabanus, the captain of his bodyguard, after a reign of 20 years.